The present invention was initially developed to attempt to provide a cost effective way for harvesting the leaves of a mallee tree for the production of mallee oil. Manual harvesting of the leaves is possible however this is seen as not economically viable. The Applicant therefore set out to develop an apparatus or machine that, in operation, could form part of a larger process culminating in the separation of the mallee leaves from the mallee tree.
It is known to harvest small trees in Europe, particularly Sweden, using a modified cane harvester made by an Australian company and modified forage harvesters made by a German company. The trees harvested are about 3 meters tall and being deciduous and cut in Winter, have no leaves.
However, the range of mallee forms is difficult to handle with existing harvesters.
The cane harvester blocks up readily and the cutting mechanism is under the machine instead of out the front. It is designed to push the cane over before cutting and the cutting elements are five bladed discs with a very aggressive chopping action.
The Claas forage harvester cuts and chips out the front, but is has a lightweight agricultural chipper, it lays the trees down in front of the saws after cutting, is prone to dropping cut stems and suffers blockages with bushy forms.
In parts of Australia, mallees are harvested with flail cutters (a mower style, but heavily built) but the mallees are short and flexible so the harvester can pass over them before cutting without dislodging the stumps. As the mallees are small it is not possible to travel fast enough to harvest a practical amount per hour and harvest costs per tonne are high.